OCS Study BOEM 2014-665 Spatiotemporal distribution and migratory patterns of Spectacled Eiders U.S. Department of the Interior Bureau of Ocean Energy Management Alaska Outer Continental Shelf Region Anchorage, Alaska This page intentionally left blank. OCS Study BOEM 2014-665 Spatiotemporal distribution and migratory patterns of Spectacled Eiders Authors: Matthew G. Sexson John M. Pearce Margaret R. Petersen Prepared under BOEM Award Interagency Agreement No. M09PG00012, AK-09-03 by USGS Alaska Science Center 4210 University Drive Anchorage, Alaska 99508 U.S. Department of the Interior Bureau of Ocean Energy Management Alaska Outer Continental Shelf Region September 2014 Disclaimer This study was funded, in part, by the U.S. Department of the Interior, Bureau of Ocean Energy Management, Environmental Studies Program, Washington, DC, under Interagency Agreement Number M09PG00012, AK-09-03 with the U.S. Geological Survey. This report has been technically reviewed by BOEM and it has been approved for publication. Any use of trade names is for descriptive purposes only and does not imply endorsement by the U.S. Government. Availability To download a PDF file of this Environmental Studies Program report, go to the U.S. Department of the Interior, Bureau of Ocean Energy Management, Environmental Studies Program Information System website and search for OCS Study BOEM 2014-665. This report can be viewed at select Federal Depository Libraries. It can also be obtained from the BOEM Alaska Outer Continental Shelf Regional Office. US Department of the Interior Bureau of Ocean Energy Management Alaska OCS Region 3801 Centerpoint Drive, Suite 500 Anchorage, AK 99503-5820 Phone: 907-334-5200 Fax: 907-334-5202 Recommended Citation Sexson, M. G., J. M. Pearce, and M. R. Petersen. 2014. Spatiotemporal distribution and migratory patterns of Spectacled Eiders. BOEM 2014-665. Bureau of Ocean Energy Management, Alaska Outer Continental Shelf Region, Anchorage, Alaska. TABLE OF CONTENTS Page List of Figures ................................................................................................................................ iii List of Tables ................................................................................................................................. iv Abbreviations and Acronyms ........................................................................................................ vi 1.0. EXECUTIVE SUMMARY ......................................................................................................1 2.0. INTRODUCTION ....................................................................................................................3 3.0. METHODS ...............................................................................................................................6 3.1. Study Sites ........................................................................................................................... 6 3.2. Transmitter Deployment ...................................................................................................... 6 3.3. Data Analysis ....................................................................................................................... 9 3.3.1. Important Areas .......................................................................................................... 10 3.3.2. Timing of Migration and Site Occupancy .................................................................. 11 3.3.3. Site Fidelity ................................................................................................................. 11 3.3.4. Migratory Connectivity ............................................................................................... 11 4.0. RESULTS ...............................................................................................................................12 4.1. Data Collection .................................................................................................................. 12 4.2. Important Areas ................................................................................................................. 13 4.3. Timing of Migration and Site Occupancy ......................................................................... 15 4.3.1. Annual Cycle Overview .............................................................................................. 15 4.3.2. Western Beaufort Sea ................................................................................................. 18 4.3.3. Eastern Chukchi Sea ................................................................................................... 21 4.3.4. East Siberian Sea......................................................................................................... 24 4.3.5. Western Bering Strait .................................................................................................. 26 4.3.6. Norton Sound .............................................................................................................. 28 4.3.7. Yukon-Kuskokwim Delta ........................................................................................... 29 4.3.8. Northern Bering Sea ................................................................................................... 30 4.4. Site Fidelity ........................................................................................................................ 32 4.4.1. Western Beaufort Sea ................................................................................................. 32 4.4.2. Eastern Chukchi Sea ................................................................................................... 36 4.4.3. East Siberian Sea......................................................................................................... 36 4.4.4. Western Bering Strait .................................................................................................. 37 i 4.4.5. Norton Sound .............................................................................................................. 37 4.4.6. Yukon-Kuskokwim Delta ........................................................................................... 37 4.4.7. Northern Bering Sea ................................................................................................... 37 4.5. Migratory Connectivity ...................................................................................................... 38 4.5.1. Connectivity Overview ............................................................................................... 38 4.5.2. Western Beaufort Sea ................................................................................................. 45 4.5.3. Eastern Chukchi Sea ................................................................................................... 45 4.5.4. East Siberian Sea......................................................................................................... 45 4.5.5. Western Bering Strait .................................................................................................. 46 4.5.6. Norton Sound .............................................................................................................. 46 4.5.7. Yukon-Kuskokwim Delta ........................................................................................... 47 4.5.8. Northern Bering Sea ................................................................................................... 47 5.0. DISCUSSION .........................................................................................................................48 5.1. Winter ................................................................................................................................ 48 5.2. Pre-breeding Migration ...................................................................................................... 53 5.3. Breeding ............................................................................................................................. 57 5.4. Post-breeding Migration .................................................................................................... 61 5.5. Management Implications .................................................................................................. 65 5.6. Considerations for Future Research ................................................................................... 66 Acknowledgements ........................................................................................................................67 Literature Cited ..............................................................................................................................68 ii List of Figures Figure 1. Satellite telemetry locations received from 89 adult (blue points, n = 6,813) and 27 juvenile (red points, n = 371) Spectacled Eiders between 30 May 2008 and 9 August 2012. We implanted satellite transmitters in Spectacled Eiders in the Yukon-Kuskokwim Delta (YKD) in 2008, at Peard Bay (PB) in 2009, and in the Colville River Delta (CRD) in 2009–2011. ..... Page 5 Figure 2. Important areas (95% Gaussian kernel density isopleths) used by Spectacled Eiders with satellite transmitters that provided data in 2008–2012. Important areas included marine and coastal habitats. ..................................................................................................................... Page 14 Figure 3. Migratory timing of Spectacled Eiders with